The present invention relates to a thermocycler for a PCR procedure.
Thermocyclers have come to be part of the basic equipment of a molecular biology lab. They are used foremost to amplify nucleic acid stretches contained in a probe in low quantity using the Polymerase Chain Reaction (PCR) procedure.
In this procedure, the specimens are sequentially subjected to three temperatures in successive cycles, namely the specimens are in a consecutive manner subjected to the temperature of denaturation of about 95° C., then to the annealing temperature of about 40° C. and then to the elongation temperature of about 70° C. In some special cases, two of theses temperature levels (i.e., the annealing temperature and the elongation temperature) may be consolidated into one temperature level.
Before many specimens can be processed on a large scale, the appropriate PCR parameters must be determined to permit the PCR be performed using optimal parameters. In this respect, it is known to vary both the temperatures at the particular levels and the reagent concentrations. Gradient cyclers are known to make temperature variation easier: these gradient cyclers apply different temperatures at different temperature levels to individual specimens.
It is known moreover that the number of cycles, i.e. the cycling rate, used in a particular PCR procedure may entail different results and hence it should be optimized. In the state of the art, however, optimizing the cycling rate is highly time-consuming because several passes, each with a different cycling rate, must be carried out consecutively in one thermocycler.